The inventive subject matter relates to circuit breakers and methods of operating the same and, more particularly, to circuit breakers with shunt trip mechanisms.
A circuit breaker typically includes at least one set of contacts and a contact actuator mechanism configured to open and close the contacts. Some circuit breakers include shunt trip mechanisms, which may be used to activate the contact actuator responsive to an externally supplied control voltage. An example of a circuit breaker incorporating such a shunt trip mechanism is the Eaton Type VCP-W medium voltage circuit breaker described in Cutler-Hammer I. B. 32-255-1F Instructions for Installation, Operation and Maintenance of Type VCP-W Vacuum Circuit Breakers (Eaton Corp., January 2000).
In some electrical distribution applications, it may be desirable to lock out a circuit breaker to prevent accidental closure of its contacts. For example, it may be desirable to prevent closure of a circuit breaker when performing maintenance or other operations in which personnel may be near circuitry fed by the circuit breaker.